Thanks meumerke for your example~ Great inspiration! I guess I should practice more with it... with the focus limiter, i'm not exactly sure how to use it properly and effectively... Do I turn the limiter on, then manually estimate the focus, and switch back to autofocus to accurately achieve focus?

The limiter is used with AF. It simply shortens the range of travel ... i.e. you can have it stay at distance and not rack all the way back to macro. Much faster when it decides to hunt.

or should I sell it and buy a Nikon 85mm f/1.8 AF-D instead? That has a screw drive AF. Would that focus faster?

The Nikon 85mm AFD is a very fine lens (I have one) and offers very high sharpness at f/2 or so ... but the Tammy is quite spectacular and it might be worth putting in a bit more time with it.

One thing I have found is that AF-S with one focal point works better than the fancy modes when there is little contrast. Also, ensure that you use a focus point directly on something contrasty like an eye. Don't try to focus on a patch of skin or hair, as there ir little contrast in that. Despite the differences between contrast AF and phase detect AF, both work much faster when contrast is high.